Welcome to an engaging session on slice manipulation in Go! Today, embark on a journey through a virtual forest represented as a slice. Your mission? To find the smallest possible jump size that allows safe passage through the forest without running into any trees. This exercise will help you strengthen your slice traversal techniques and problem-solving skills. Let the adventure begin!

Consider a slice that symbolizes a dense forest; each index is either 1, indicating a tree, or 0, signifying a clear position. Starting from a fixed initial index and given a specific direction, your objective is to ascertain the smallest possible jump size that enables traversal from the initial position to one of the ends of the slice without hitting a tree. Each move you make will be exactly the determined jump size in the given direction.

Keep these points in mind:

• The slice of binary integers (0 and 1) depicts the forest.
• The direction is an integer. 1 implies jumping toward larger indices, while -1 denotes jumping toward smaller ones.
• In situations where there is no jump size that can avoid all trees, return -1 to indicate the impossibility of traversal under these conditions.

The ultimate objective? Identify the minimal jump size that ensures smooth navigation through the entire forest without hitting a single tree.